Electrostatic storage system



Nov. 2, 1965 R. LUBOW 3,215,911

ELECTROSTATIC STORAGE SYSTEM Filed Sept. 5. 1961 UTILIZATION DEVICE r9 .1 /6-. 4. INVENTOR.

RAYMOND LUBOW United States Patent 3,215,911 ELECTROSTATIC STORAGE SYSTEM Raymond Lubow, 17007 Merit Ave.,'Gardena, Calif. Filed Sept. 5, 1961, Ser. No. 136,097 8 Claims. (Cl. 317-262) This invention relates to systems for storing electrical signals and, more particularly, to improvements therein.

An object of this invention is the provision of an improved electrostatic storage system.

Another object of this invention is the provision of a novel electrostatic storage system of the type employing a moving dielectric medium.

Yet another object of the present invention is the provision of a dielectric storage system using a moving dielectric wherein the effects of noise-signal wear are minimized.

These and other obejcts of the invention may be achieved in an arrangement wherein a moving dielectric, employed for an electrostatic storage system in accordance with this invention, is rotatably supported within a container. The container also holds a lubricating fluid in a manner so that the moving dielectric may be continuously lubricated while it is moving. Furthermore, by selection of the type of fluid employed and its conductivity characteristics, an improved operation for this storage system is achieved.

The novel features that are considered characteristic of this invention are set forth with particularity in the appended claims. The invention itself, both as to its organization and method of operation, as well as additional objects and advantages thereof, will best be understood from the following description when read in connection with the accompanying drawings, in which:

FIGURE 1 is a drawing of an embodiment of the invention taken along the lines 11 of FIGURE 2;

FIGURE 2 is a side view, illustrating further details of the embodiment of the invention; and

FIGURE 3 is a drawing of an embodiment of the invention using a planar surface instead of a cylindrical surface.

Referring now to FIGURES 1 and 2 of the drawing,

which illustrate the invention, it includes a motor 10 having a shaft 12 which extends into a container 14. Inside the container the shaft supports a cylinder 16. The container 14 has a hole sufiiciently large to enable the shaft 12 to pass therethrough without coming in contact with the container. Supports 20, 22 hold the motor in fixed position relative to the container, so that the motor, when energized, can rotate the shaft 12 and therewith the cylinder 16, without rotating the container 14. There is r a cover 24 at one side of the container to afford access to its interior.

Referring now to FIGURE 2, the periphery of the cylinder 16 comprises a dielectric surface 20, which has a conductive backing 18. A preferred arrangement comprises making the cylinder, or at least the conductive backing portion thereof, of aluminum, with the outer periphery, or dielectric surface 20, made of aluminum oxide formed by anodizing the aluminum. Extending through the container 14 to afford electrical communication with the interior thereof is a write electrode 26 and a read electrode 28. These electrodes may be any suitable material extending into the container, in order to afford an electrical connection with the surface of the dielectric. It has been found that conductive rubber, which comprises rubber impregnated with graphite, will aflord both the electrical connection to the surface of the dielectric and yet be sufficiently soft not to gouge the surface of the dielectric as it is rotated past these electrodes.

3,215,911 Patented Nov. 2, 1965 There is, however, a certain amount of friction present because of the pressure required between the reading and writing electrode and the dielectric, in order to afford an intimate contact therebetween and minimize the signal loss. Compensation for this friction must be made, or the life expectancy of the arrangement is rather minimal. Other effects of the friction are that electrons may be displaced along the surface of the dielectric which can manifest their presence as a noticeable potential which covers the surface of the dielectric. This potential serves no useful purpose and produces undesirable noise, which is distinctly present in any signals which are read from this dielectric memory.

'In accordance with this invention, to minimize this potential, not only is friction reduced, but, further, by providing the greatest possible useful capacitance for a given area in which friction occurs, since the same number of-electrons are displaced whether the capacitance per given area is large or small, the displaced electrons within the large capacitance have a much lesser effect than heretofore on signals which are read from the memory. In order to both provide lubrication and to increase the amount of electrical capacitance for the friction area presented, there is provided a lubricating fluid 30, which is poured into the bottom of the container 14 through the opening provided when the cover 24 is removed. Suflicient fluid is poured into the container so that the cylinder '16 will dip into the fluid as it rotates. There is provided a wiper 32 for removing excess lubricating fluid and for leaving a thin film on the surface of the cylinder. The wiper 32 may be of any soft material which still has sufficient rigidity to remove the excess fluid. The wiper is supported from the container.

The lubricant 30 may be an electrically conductive fluid which will cover the dielectric in the form of a thin film. The conductivity of the fluid allows electrical energy to pass between the electrode and the dielectric and thereby forms a more intimate electrical contact, minimizing the effects of porosity and irregularities in the dielectric. Also, it enlarges the size of the useful capacitance in the region of friction. The conductivity of the lubricating fluid, however, should not be such as to cause a discharge between the reading and writing electrodes. A preferred resistance for the fluid is one which ranges between 10 megohms per cubic centimeter to 200 megohms per cubic centimeter. A preferred fluid which provides both the lubricating and the conductive qualities desired is a polyalkylene oxide derivative, which is sold by the Union Carbide Company under the trade name of Ucon LB 65 fluid. This fluid is mixed with alcohol until its conductivity reaches a desired value. However, any lubricating fluid having the desired conductivity may be used, instead.

The write signals are applied from the write-signal source 34 to the write electrode, which must be insulatingly supported from the container if the container is made of a conductive material. The write electrode applies these signals to the dielectric surface, which carries them around as the dielectric surface is rotated until the read electrode is reached. The read electrode must also be insulatingly supported if the container is made of metal or other conductive material. The read electrode is connected to a utilization device 36, which makes use of these signals. It should be noted that the conductive backing must be grounded, in order to complete the circuit between the write-signal source and the utilization device. The rotating dielectric and the fluid lubricant are completely enclosed in the container, thereby preventing evaporation of the fluid. Although the configuration shown causes lubrication to be achieved by actually dipping the dielectric surface into the lubricant as it rotates,

alternative arrangements, such as using a wick or wiper 32 soaked with the fluid, can be used. The wiper may be immersed in the fluid, and through capillary action it applies the fiuid to the surface of the dielectric. Other arrangements may be applying fluid byspray or drip arrangements within the container. It should be noted that the present arrangement is shown by way of exemplification.

FIGURE 3 shows an embodiment of the invention wherein the moving dielectric has the form of a planar surface 40 or disc, rotatably supported in a vertical plane by the shaft 12 of the motor within the container 14. As described in connection with FIGURE 1, a write electrode 26 and a read electrode 28 are in contact with the surface of the dielectric and are also connected by any suitable leads to the outside of the container 14. The dielectric surface dips into the lubricating and conductive fluid 30 in the reservoir formed in the bottom of the container 14, and a wiper 32 removes excess fluid and leaves only a thin film.

There has accordingly been shown and described herein a novel, useful, and simple arrangement for considerably extending the life of an electrostatic storage system which employs a moving dielectric medium. By this arrangement the performance of this type of storage system is improved, since, by selecting the lubricating fluid with the proper electrical properties, noise signals are considerably reduced, and effectively a better transfer of the electrical signals from an electrode to the dielectric and from the dielectric to the electrode is elfectuated. The cylindrical drum or planar configuration is shown by way of a preferred example and is not to be construed as a limitation on the invention without departing from the spirit and scope of this invention. Other forms may be used or the dielectric and conductive backing thereof may be in the form of a tape which dips into a reservoir of conductive lubricating fluid to be lubricated before coming under the writing and reading electrodes.

I claim:

1. An electrostatic storage system comprising a movable conductive surface, a dielectric material covering said surface, first electrode means for applying signals to said dielectric material, second electrode means spaced from said first electrode means for removing signals from said dielectric material, means for moving said movable conductive surface for moving said dielectric material past said first and second electrode means, a lubricating fluid having a predetermined conducivity, and means for continuously applying said fluid to said dielectric material in a thin film to be present at said first and second electrode means.

2. An electrostatic storage system as recited in claim 1 wherein said means for continuously applying said fluid to said dielectric material in a thin film includes a reservoir for said fluid through which said dielectric material on said movable conductive surface is moved, and brush means for removing any fluid excess after said dielectric material has passed through said reservoir.

3. In an electrostatic storage system of the type wherein a movable dielectric surface is successively passed under a writing and reading electrode the improvement comprising a conductive lubricating fluid, and means for applying said fluid to said movable dielectric surface in a thin film prior to passing under said electrodes.

4. An electrostatic storage system comprising a conductive body in the shape of a figure of revolution, said body having the outer surface thereof covered with a dielectric material, means for rotatably supporting said body, a first electrode for applying signals to said dielectric material, means for holding said first electrode in contact with said dielectric material, a second electrode for removing signals from said dielectric material, means for holding said second electrode in contact with said dielectric material, said second electrode being positioned at a distance from said first electrode, a lubricating fluid having a predeter mined conductivity, and means for applying said lubricating fluid to said dielectric material in a thin film.

5. A dielectnic storage system comprising a conductive cylindrical body, a dielectric material covering the outer periphery of said cylindrical body, a container, means for rotatably supporting said cylindrical body within said container, first electrode means for affording electrical connection with said dielectric through said container, second electrode means for affording electrical connection with said dielectric through said container, and a lubricating fluid having a predetermined conductivity, said lubricating fluid being within said container in an amount sufficient to insure that the dielectric surface of said cylinder comes in contact therewith.

6. The electrostatic storage apparatus recited in claim 5 wherein said lubricating fluid is a mixture of a polyalkylene oxide derivative .and alcohol.

7. An electrostatic storage apparatus as recited in claim 5 wherein said means for rotatably supporting said cylindrical member within said container comprises a motor, means for supporting said motor from said container, said motor having a shaft extending into said container and attached to said cylindrical member providing support therefor.

8. An electrostatic storage apparauts comprising an aluminum drum having the outer periphery thereof oxidized, a container, means for rotatably supporting said aluminum drum within said container, a first electrode made of conductive rubber, means for supporting said first electrode from said container to be in contact with the surface of said aluminum drum and to provide an external connection thereto, a second electrode made of conductive rubber, means for supporting said second elec trode from said container to be in contact with said aluminum drum surface and to afford external electrical connection thereto, a lubricating fluid within said container, said lubricating fluid being in sufficient quantity to insure that the periphery of said drum will dip thereinto and be wetted thereby, a wiper supported from said container to be incontact with the periphery of said drum for removing any excess of said lubricating fluid from the surface of said drum as said drum is rotated, means for applying an electrical signal to said first electrode, and means for deriving an electrical signal from said second electrode.

References Cited by the Examiner UNITED STATES PATENTS 2,892,973 6/59 Straughan 346-74 3,060,431 10/62 Fuller et al. 179-l00.2

SAMUEL BERNSTEIN, Primary Examiner. 

1. AN ELECTROSTATIC STORAGE SYSTEM COMPRISING A MOVABLE CONDUCTIVE SURFACE, A DIELECTRIC MATERIAL COVERING SAID SURFACE, FIRST ELECTRODE MEANS FOR APPLYING SIGNALS TO SAID DIELECTRIC MATERIAL, SECOND ELECTRODE MEANS SPACED FROM SAID FIRST ELECTRODE MEANS FOR REMOVING SIGNALS FROM SAID DIELECTRIC MATERIAL, MEANS FOR MOVING SAID MOVABLE CONDUCTIVE SURFACE FOR MOVING SAID DIELECTRIC MATERIAL PAST SAID FIRST AND SECOND ELECTRODE MEANS, A LUBRICATING FLUID HAVING A PREDETERMINED CONDUCTIVITY, AND MEANS FOR CONTINUOUSLY APPLYING SAID FLUID TO SAID DIELECTRIC MATERIAL IN A THIN FILM TO BE PRESENT AT SAID FIRST AND SECOND ELECTRODE MEANS. 